CN112940213A

CN112940213A - Polyurea resin

Info

Publication number: CN112940213A
Application number: CN202011347520.1A
Authority: CN
Inventors: 增渕徹夫; 大谷哲也
Original assignee: Asahi Kasei Corp
Current assignee: Asahi Kasei Corp
Priority date: 2019-11-26
Filing date: 2020-11-26
Publication date: 2021-06-11
Anticipated expiration: 2040-11-26
Also published as: JP2021088705A; CN112940213B; EP3828215B1; EP3828215A1

Abstract

The purpose of the present invention is to provide a polyurea resin that has excellent flexibility, strength, abrasion resistance, chemical resistance, and low-temperature characteristics. A polyurea resin which is a reaction product of a polyisocyanate compound (a), a polycarbonate diol (b) and a chain extender (c), wherein the polyisocyanate compound (a) is an organic polyisocyanate compound having an average number of isocyanate groups of 2.5 or less in 1 molecule, the polycarbonate diol (b) has a repeating unit represented by a specific formula (1) and a terminal hydroxyl group, the content of a carbonate group contained in 1 molecule in the polycarbonate diol (b) is 41.5 to 45.7 mass%, the number average molecular weight is 900 to 3100g/mol, and the chain extender (c) is a diamine.

Description

Polyurea resin

Technical Field

The present invention relates to polyurea resins.

Background

Conventionally, polyurethane resins and polyurea resins have been used in a wide range of fields such as synthetic leathers, artificial leathers, adhesives, furniture coatings, and automobile coatings, and polyethers and polyesters have been used as polyol components that react with isocyanates (see, for example, patent documents 1 to 2). However, in recent years, there has been an increasing demand for resin resistance such as heat resistance, weather resistance, hydrolysis resistance, mold resistance, and oil resistance.

As a soft segment excellent in hydrolysis resistance, light resistance, oxidation deterioration resistance, heat resistance and the like, a polycarbonate diol of 1, 6-hexanediol is commercially available, which exhibits the above-mentioned characteristics because a carbonate bond in a polymer chain is chemically extremely stable. However, the polycarbonate diol formed from 1, 6-hexanediol is solid at room temperature and has high crystallinity, and therefore, the thermoplastic polyurethane obtained has a disadvantage of poor flexibility. For the purpose of improving the flexibility of the obtained thermoplastic polyurethane, for example, patent document 3 proposes a polycarbonate diol obtained by copolymerizing 1, 6-hexanediol with 1, 4-butanediol. Further, for example, patent document 4 proposes a polycarbonate diol obtained by copolymerizing 1, 6-hexanediol with 1, 5-pentanediol. Thermoplastic polyurethanes using these copolycarbonate diols are also excellent in flexibility and low-temperature characteristics, and have attracted attention in recent years.

For example, patent document 5 proposes polycarbonate diol and thermoplastic polyurethane produced using 1, 3-propanediol as a main diol raw material. Since the polycarbonate diol produced using 1, 3-propanediol as the main diol raw material is liquid at room temperature and exhibits non-crystallinity, the resulting thermoplastic polyurethane has excellent flexibility. In addition, since the carbonate group also has a high density, it is characterized by excellent abrasion resistance and chemical resistance.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2000-95836

Patent document 2: japanese patent laid-open No. 2001-123112

Patent document 3: japanese laid-open patent publication No. 5-51428

Patent document 4: japanese laid-open patent publication No. 6-49166

Patent document 5: international publication No. 2002/070584

Disclosure of Invention

Problems to be solved by the invention

However, there is still room for improvement in abrasion resistance and chemical resistance of thermoplastic polyurethanes using copolymerized polycarbonate diols obtained from 1, 6-hexanediol and 1, 4-butanediol or 1, 5-pentanediol, which are described in patent documents 3 and 4.

In addition, the thermoplastic polyurethane described in patent document 5 has a problem in low temperature characteristics because the polycarbonate diol used has a high carbonate group density, and therefore has low molecular mobility, and there is room for improvement in flexibility, and the glass transition temperature is also high.

Accordingly, an object of the present invention is to provide a polyurea resin having excellent flexibility, strength, abrasion resistance, chemical resistance and low-temperature characteristics, which cannot be achieved by a thermoplastic polyurethane obtained by using a conventional polycarbonate diol.

Means for solving the problems

The inventors of the present invention have conducted extensive studies and found that: the present inventors have completed the present invention by obtaining a polyurea resin which can solve the above problems by combining a specific organic polyisocyanate compound, a polycarbonate diol having a specific structure, and a specific chain extender.

That is, the present invention includes the following aspects.

[1] A polyurea resin which is a reaction product of a polyisocyanate compound (a), a polycarbonate diol (b) and a chain extender (c),

the polyisocyanate compound (a) is an organic polyisocyanate compound having an average number of isocyanate groups in 1 molecule of 2.5 or less,

the polycarbonate diol (b) has a repeating unit represented by the following formula (1) and a terminal hydroxyl group,

the polycarbonate diol (b) has a carbonate group content of 41.5 to 45.7 mass% in 1 molecule and a number average molecular weight of 900 to 3100g/mol,

the chain extender (c) is a diamine.

(in the formula, R₁Represents a divalent aliphatic hydrocarbon or alicyclic hydrocarbon having 2 to 20 carbon atoms. )

[2] The polyurea resin according to [1], wherein in the (b) polycarbonate diol, 20 mol% or more of the repeating units represented by the formula (1) are repeating units represented by the following formula (2), and 20 mol% or more of the repeating units represented by the formula (1) are repeating units represented by the following formula (3).

[3] The polyurea resin according to [1] or [2], wherein the polyisocyanate compound (a) is an alicyclic polyisocyanate.

[4] The polyurea resin according to any one of [1] to [3], wherein the chain extender (c) is an alicyclic diamine.

[5] A polyurea resin film obtained by molding the polyurea resin according to any one of [1] to [4] in a film form, the polyurea resin film having a thickness of 10 μm to 500 μm.

[6] A synthetic leather using the polyurea resin according to any one of [1] to [4 ].

ADVANTAGEOUS EFFECTS OF INVENTION

The polyurea resin is excellent in flexibility, strength, abrasion resistance, chemical resistance and low-temperature characteristics.

Detailed Description

Hereinafter, a mode for carrying out the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[ polyurea resin ]

The polyurea resin of the present embodiment is a reaction product of a polyisocyanate compound (a), a polycarbonate diol (b), and a chain extender (c),

the chain extender (c) is a diamine.

The polyurea resin of the present embodiment is excellent in flexibility, strength, abrasion resistance, chemical resistance, and low-temperature characteristics by combining a specific organic polyisocyanate compound, a specific structure of a polycarbonate diol, and a specific chain extender.

[ polyisocyanate Compound (a) >

The component (a) used in the polyurea resin of the present embodiment is an organic polyisocyanate compound having less than 2.5 isocyanate groups in 1 molecule. Specific examples of such organic polyisocyanate compounds are not particularly limited, and include known aromatic diisocyanates such as 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate and a mixture Thereof (TDI), diphenylmethane-4, 4 ' -diisocyanate (MDI), naphthalene-1, 5-diisocyanate (NDI), 3 ' -dimethyl-4, 4 ' -biphenyl diisocyanate, crude TDI, polymethylene polyphenyl isocyanate, crude MDI, etc.; known aromatic alicyclic diisocyanates such as Xylylene Diisocyanate (XDI) and xylylene diisocyanate; known aliphatic diisocyanates such as 4, 4' -methylenedicyclohexyldiisocyanate (hydrogenated MDI), Hexamethylene Diisocyanate (HDI), isophorone diisocyanate (IPDI), and cyclohexane diisocyanate (hydrogenated XDI), and isocyanurated, carbodiimidized, and biuretized modifications of these isocyanates. Among them, the polyisocyanate compound (a) used in the present embodiment is preferably an alicyclic polyisocyanate. When the polyisocyanate is an alicyclic polyisocyanate, the polyurea resin obtained tends to be excellent in strength, abrasion resistance and chemical resistance. From the viewpoint of strength and abrasion resistance of the polyurea resin obtained, diphenylmethane-4, 4 ' -diisocyanate (MDI), Hexamethylene Diisocyanate (HDI), isophorone diisocyanate (IPDI), and 4,4 ' -methylenedicyclohexyl diisocyanate (hydrogenated MDI) are particularly preferable, and among them, isophorone diisocyanate (IPDI) and 4,4 ' -methylenedicyclohexyl diisocyanate (hydrogenated MDI) having excellent weather resistance are particularly preferable.

In the organic polyisocyanate compound, the average number of isocyanate groups in 1 molecule is preferably 1.9 to 2.5, more preferably 2.0 to 2.3.

In the present embodiment, the average number of isocyanate groups (average number of functional groups) in 1 molecule of the organic polyisocyanate compound can be determined from the following formula based on the content (mass%) of isocyanate groups determined by the method described in JIS K7301-1995 and the number average molecular weight of the organic polyisocyanate determined by measuring the number average molecular weight based on polystyrene by Gel Permeation Chromatography (GPC).

Average functional group number (number average molecular weight of organic polyisocyanate) × isocyanate group content (% by mass)/100%/42%

Specific analysis methods of the isocyanate group content and the number average molecular weight of the organic polyisocyanate are shown below.

(Property 1) content of isocyanate group

The content of isocyanate groups in a polyisocyanate composition used as a sample was measured according to the method described in JIS K7301-1995 (test method for a toluene diisocyanate type prepolymer for a thermosetting urethane elastomer). Hereinafter, a more specific method for measuring the content of isocyanate groups will be described.

(1) A1 g sample was collected in a 200mL Erlenmeyer flask, and 20mL of toluene was added to the flask to dissolve the sample.

(2) Then, 20mL of a 2.0N di-N-butylamine/toluene solution was added to the flask, and the mixture was allowed to stand for 15 minutes.

(3) To the flask was added 70mL of 2-propanol, and the mixture was dissolved to obtain a solution.

(4) The solution obtained in (3) above was titrated with 1mol/L hydrochloric acid to obtain the amount of sample titration.

(5) In the case where no sample was added, measurement was performed by the same method as in (1) to (3) above to obtain a blank titration amount.

From the sample dropping amount and the blank dropping amount obtained above, the isocyanate group content was calculated by the following calculation method.

The isocyanate group content (% by mass) is (blank titration amount-sample titration amount) x 42/[ sample mass (g) x1,000 ] x 100%.

(Property 2) number average molecular weight of organic polyisocyanate

The number average molecular weight of the polyisocyanate including the modified polyisocyanate and the unreacted polyisocyanate in the polyisocyanate composition was measured by Gel Permeation Chromatography (GPC) using the following apparatus and conditions.

The device comprises the following steps: HLC-8120GPC (trade name) manufactured by Tosoh corporation

Column: TSKgelSuperH1000 (trade name). times.1, TSKgelSuperH2000 (trade name). times.1, TSKgelSuperH3000 (trade name). times.1, manufactured by Tosoh corporation,

carrier: tetrahydrofuran (THF)

The detection method comprises the following steps: differential refractometer

(Property 3) average number of isocyanate functional groups

The average number of isocyanate functional groups of a polyisocyanate composition as a sample was calculated as shown below from the number average molecular weight of the organic polyisocyanate measured in (Property 2) and the isocyanate group content measured in (Property 1) based on the number average molecular weight of the organic polyisocyanate statistically having isocyanate functional groups in the molecule of polyisocyanate 1.

[ polycarbonate diol (b) >

The polycarbonate diol (b) used in the polyurea resin of the present embodiment has a repeating unit represented by the following formula (1) and a terminal hydroxyl group, and the polycarbonate diol (b) has a carbonate group content of 41.5 to 45.7 mass% in 1 molecule and a number average molecular weight of 900 to 3100 g/mol.

The raw material diol for producing the polycarbonate diol (b) is not particularly limited, and diols having no side chain such as ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol, 1, 11-undecanediol, 1, 12-dodecanediol, and 1, 14-tetradecanediol; diols having a side chain such as 2-methyl-1, 8-octanediol, 2-ethyl-1, 6-hexanediol, 2-methyl-1, 3-propanediol, 3-methyl-1, 5-pentanediol, 2, 4-dimethyl-1, 5-pentanediol, 2, 4-diethyl-1, 5-pentanediol, 2-butyl-2-ethyl-1, 3-propanediol, and 2, 2-dimethyl-1, 3-propanediol; 1 or 2 or more kinds of cyclic diols such as 1, 4-cyclohexanedimethanol and 2-bis (4-hydroxycyclohexyl) propane.

In addition, a small amount of a compound having 3 or more hydroxyl groups in 1 molecule, for example, trimethylolethane, trimethylolpropane, hexanetriol, pentaerythritol, or the like may be used. When the compound having 3 or more hydroxyl groups in 1 molecule is used in an excess amount, crosslinking may proceed during the polymerization reaction of the polycarbonate to cause gelation. Therefore, the compound having 3 or more hydroxyl groups in 1 molecule is preferably 0.01 to 5% by mass based on the total amount of the aliphatic diol and/or the alicyclic diol. More preferably 0.01 to 1 mass%.

As the polycarbonate diol (b) used in the present embodiment, a polycarbonate diol in which 1, 4-butanediol and 1, 6-hexanediol are used as raw materials is particularly preferable. Specifically, among the polycarbonate polyols of the above (b), preferred are: the proportion of the repeating unit represented by the following formula (2) derived from 1, 4-butanediol in the repeating unit represented by the formula (1) is preferably 20 mol% or more, more preferably 20 mol% or more and 90 mol% or less, further preferably 35 mol% or more and 65 mol% or less, and the proportion of the repeating unit represented by the following formula (3) derived from 1, 6-hexanediol in the repeating unit represented by the formula (1) is preferably 20 mol% or more, more preferably 20 mol% or more and 90 mol% or less, further preferably 35 mol% or more and 65 mol% or less.

The method for producing the polycarbonate diol (b) used in the present embodiment is not particularly limited. For example, the polymer can be produced by various methods described in Schnell, Polymer-reviews (Polymer-reviews) volume 9, and p 9-20 (1994).

Examples of the production method include, but are not particularly limited to, the following methods: mixing a carbonate raw material described later with the above diol raw material, reacting the mixture at 100 to 200 ℃ in the presence of a transesterification catalyst under normal pressure or reduced pressure to remove the produced alcohol derived from the carbonate raw material to obtain a low molecular weight polycarbonate diol, and then heating the mixture at 160 to 250 ℃ under reduced pressure to condense the low molecular weight polycarbonate diol while removing unreacted carbonate raw material and diol, thereby obtaining a polycarbonate diol having a predetermined molecular weight.

The carbonate raw material used for the synthesis of the (b) polycarbonate diol used in the present embodiment is not particularly limited, and examples thereof include dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate; diaryl carbonates such as diphenyl carbonate; alkylene carbonates such as ethylene carbonate, 1, 3-propylene carbonate, 1, 2-butylene carbonate, 1, 3-butylene carbonate, and 1, 2-pentylene carbonate. 1 or 2 or more carbonates among these can be used as a raw material. From the viewpoint of ease of obtaining and ease of setting conditions for the polymerization reaction, dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, and dibutyl carbonate are more preferably used.

The production of the polycarbonate diol (b) used in the present embodiment is usually carried out by adding a catalyst. The catalyst used in the present embodiment can be freely selected from general transesterification catalysts. For example, metals, salts, alkoxides, and organic compounds such as lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, and cerium can be used. Particularly preferred are compounds of titanium, tin and lead. In addition, the amount of the catalyst used is usually 0.00001 to 0.1% by mass based on the polycarbonate diol.

The polycarbonate diol (b) used in the polyurea resin of the present embodiment has a carbonate group content in 1 molecule of 41.5 to 45.7 mass%, more preferably 42.2 to 44.3 mass%, and still more preferably 42.8 to 43.8 mass%.

The carbonate group content is the amount of carbonate groups contained in 1 molecule of polycarbonate diol, and is specifically determined by the following formula (I).

Carbonate group content (%) - (molecular weight of carbonate group) × (number of repeating units in 1 molecule)/(number average molecular weight of polycarbonate diol) × 100 (I)

(Here, the molecular weight of the carbonate group (-O-C. O-) was 60.01.)

When the content of the carbonate group contained in 1-molecule polycarbonate diol is not less than the lower limit, the polyurea resin obtained is improved in chemical resistance and abrasion resistance. When the content of the carbonate group in the 1-molecule polycarbonate diol is not more than the upper limit, the flexibility and low-temperature characteristics of the polyurea resin obtained are improved.

In the present embodiment, the content of the carbonate group contained in 1-molecule polycarbonate diol can be measured by the method described in the examples below.

The number average molecular weight of the polycarbonate polyol (b) used in the present embodiment is 900 to 3100g/mol, preferably 1400 to 2600g/mol, and more preferably 1800 to 2200 g/mol. When the number average molecular weight of the polycarbonate polyol (b) is not less than the lower limit, the flexibility of the polyurea resin obtained is improved. When the number average molecular weight of the polycarbonate polyol (b) is not more than the upper limit, the wear resistance and chemical resistance of the polyurea resin obtained are improved.

The method for controlling the number average molecular weight of the polycarbonate polyol (b) to the above range is not particularly limited, and examples thereof include the following methods: a polycarbonate raw material and a diol raw material are mixed, and the mixture is reacted at 100 to 200 ℃ in the presence of a transesterification catalyst under normal pressure or reduced pressure to remove the produced alcohol derived from the carbonate raw material to obtain a low molecular weight polycarbonate diol, and then the low molecular weight polycarbonate diol is condensed while removing the unreacted carbonate raw material and diol by heating at 160 to 250 ℃ under reduced pressure to obtain a polycarbonate diol having a predetermined molecular weight. Here, the number average molecular weight of the polycarbonate diol can be adjusted according to the amount of diol distilled off by condensing the low molecular weight polycarbonate diol.

In the present embodiment, the number average molecular weight of the polycarbonate polyol (b) can be measured by the method described in the examples below.

< c chain extender >

The chain extender (c) used in the polyurea resin of the present embodiment is a diamine. Specific examples thereof include, but are not particularly limited to, diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, tolylenediamine, xylylenediamine, diphenyldiamine, diaminodiphenylmethane, 4 ' -methylenebis (cyclohexylamine), piperazine, Isophoronediamine (IPDA), and 3,3 ' -dichloro-4, 4 ' -diaminodiphenylmethane (MOCA). From the viewpoint of obtaining a polyurea resin excellent in tensile breaking strength, abrasion resistance, chemical resistance, and weather resistance, the chain extender (c) is more preferably an alicyclic diamine, and specifically, 4 ' -methylenebis (cyclohexylamine), Isophoronediamine (IPDA), and 3,3 ' -dichloro-4, 4 ' -diaminodiphenylmethane (MOCA) are preferable.

< method for synthesizing polyurea resin >

The polyurea resin of the present embodiment can be synthesized by the following method: a method of simultaneously reacting a polyisocyanate compound (a) with three kinds of a polycarbonate diol (b) and a chain extender (c); and a method in which the polyisocyanate compound (a) and the polycarbonate diol (b) are reacted in advance to prepare a prepolymer, and then a chain extender (c) is added to the prepolymer to extend the chain.

In addition to the components (a) to (c), other components, for example, a carboxyl group-and/or sulfo group-containing polyol (d) described later, or a salt thereof, or a known polyol may be used in combination as a raw material for synthesizing the polyurea resin of the present embodiment within a range not impairing the effect of the present invention.

When the polyisocyanate compound (a) is simultaneously reacted with three kinds of the polycarbonate diol (b) and the chain extender (c), the compounding ratio is preferably such that the ratio of the total equivalent of the hydroxyl groups of the polycarbonate diol (b) and the amino groups of the chain extender (c) to the NCO equivalent of the polyisocyanate compound (a) (total equivalent of hydroxyl groups and amino groups)/NCO equivalent is 1/0.5 to 1/1.5, and more preferably such that the ratio of the total equivalent of hydroxyl groups and amino groups)/NCO equivalent is 1/0.8 to 1/1.2. The amount of the chain extender (c) added when the three types of the polyisocyanate compound (a), the polycarbonate diol (b) and the chain extender (c) are simultaneously reacted is preferably 3 to 40% by mass, more preferably 5 to 25% by mass, based on the total mass of the polycarbonate diol (a) and the polyisocyanate (b).

In the case of using a method in which the polyisocyanate compound (a) and the polycarbonate diol (b) are reacted in advance to prepare a prepolymer, and then the chain extender (c) is added to the prepolymer for chain extension, the polycarbonate diol (b) and the polyisocyanate compound (a) are preferably synthesized at a compounding ratio OH/NCO (equivalent ratio) of 1/1.5 to 2.5, more preferably at a compounding ratio OH/NCO (equivalent ratio) of 1/1.8 to 2.2, and then the chain extender (c) is added to the prepolymer obtained at 1 equivalent of NCO with preferably 0.5 to 1.5, more preferably 0.8 to 1.2, of amino equivalent for chain extension.

In addition, the polyurea resin of the present embodiment may be synthesized in an aqueous system. The method for synthesizing the polyurea resin in the aqueous system (method for producing the aqueous polyurea resin) is not particularly limited, and the following methods can be exemplified. An aqueous polyurea dispersion can also be prepared by synthesizing a prepolymer from (a)1 an organic polyisocyanate compound containing 2 or more isocyanate groups in the molecule, (b) a polycarbonate diol, and (d) a polyol or a salt thereof containing a carboxyl group and/or a sulfo group, preferably at a compounding ratio OH/NCO (equivalent ratio) of 1/1.5 to 2.5, more preferably at a compounding ratio OH/NCO (equivalent ratio) of 1/1.8 to 2.2, in the presence or absence of an organic solvent (e.g., acetone, methyl ethyl ketone, tetrahydrofuran, N-dimethylformamide, etc.) not containing an active hydrogen-containing group in the molecule, dispersing the prepolymer in water, and then adding a diamine as the chain extender (c). The reaction solution thus obtained may be dispersed by adding it while stirring in water, and then the solvent may be removed as necessary to obtain an aqueous polyurea dispersion.

(d) The carboxyl group-and/or sulfo group-containing polyol or a salt thereof is a component used for the purpose of introducing a carboxylate group or a sulfonate group to self-emulsify the water-dispersible polyurea in water and to impart dispersion stability to the aqueous polyurea dispersion. The carboxyl group-containing polyol is not particularly limited, and examples thereof include 2, 2-dimethylolpropionic acid (DMPA), 2-dimethylolbutyric acid, 2-dimethylolheptanoic acid, 2-dimethyloloctanoic acid, and the like. Examples of the sulfo group-containing polyol include sulfonic acid diol {3- (2, 3-dihydroxypropoxy) -1-propanesulfonic acid } and sulfamic acid diol { N, N-bis (2-hydroxyethyl) sulfamic acid } and alkylene oxide adducts thereof. The salt of the carboxyl group-and/or sulfo group-containing polyol is not particularly limited, and examples thereof include ammonium salts, amine salts [ salts of primary amines having 1 to 12 carbon atoms (primary monoamines such as methylamine, ethylamine, propylamine, and octylamine), salts of secondary monoamines (dimethylamine, diethylamine, and dibutylamine), salts of tertiary monoamines (aliphatic tertiary monoamines such as trimethylamine, triethylamine triethanolamine, N-methyldiethanolamine, and N, N-dimethylethanolamine, heterocyclic tertiary monoamines such as N-methylpiperidine and N-methylmorpholine, benzyldimethylamine, α -methylbenzyldimethylamine, and salts of tertiary monoamines containing an aromatic ring such as N-dimethylaniline) ], salts of alkali metals (sodium, potassium, and lithium cations), and combinations of 2 or more of these.

(d) The amount of the carboxyl group and/or sulfo group-containing polyol or salt thereof is preferably an amount such that the carboxyl group and/or sulfo group is 0.01 to 10 mass% based on the mass of the polyurea resin. (d) The amount of the carboxyl group and/or sulfo group-containing polyol or salt thereof is more preferably 0.1 to 7% by mass, and still more preferably 0.5 to 5% by mass, of the carboxyl group and/or sulfo group relative to the mass of the polyurea resin. When the carboxyl group and/or the sulfo group is 0.01 mass% or more based on the mass of the polyurea resin, the emulsion stability tends to be more excellent. Further, when the carboxyl group and/or the sulfo group is 10 mass% or less based on the mass of the polyurea resin, the water resistance of the obtained coating film tends to be more excellent.

Further, the polycarbonate diol (b) used in the present embodiment may be used in combination with a known polyol within a range not impairing the effects of the present invention. Known polyols include known polyols such as polyesters and polyethers described in Kyofu, Proc.1987, and Proc.12 to 23 of polyurethane foam polymers.

As a method for producing the polyurea resin of the present embodiment, a conventionally known technique of a urethanization reaction can be used. For example, the polyurea resin of the present embodiment can be produced by reacting the polycarbonate diol (b), the polyisocyanate compound (a), and the chain extender (c) at room temperature to 200 ℃.

In their production, known polymerization catalysts represented by tertiary amines, organic metal salts of tin, titanium, and the like "described, for example, in Jitian's treatise (polyurethane resin) on pages 23 to 32 (1969)" may be used. The reaction can be carried out using a solvent, and preferable solvents include dimethylformamide, diethylformamide, dimethylacetamide, dimethylsulfoxide, tetrahydrofuran, methyl isobutyl ketone, dioxane, cyclohexanone, benzene, toluene, and ethyl cellosolve.

In addition, in the production of the polyurea resin of the present embodiment, as the blocking agent, a compound containing only one active hydrogen which reacts with an isocyanate group, for example, a monohydric alcohol such as ethanol or propanol; primary amines such as n-propylamine, n-butylamine, n-pentylamine, and n-hexylamine; and secondary amines such as diethylamine and di-n-propylamine.

As the additive used in the present embodiment, a stabilizer such as a heat stabilizer or a light stabilizer is preferably used. The heat stabilizer is not particularly limited, and examples thereof include phosphorus compounds such as aliphatic, aromatic or alkyl-substituted aromatic esters of phosphoric acid and phosphorous acid, hypophosphorous acid derivatives, phenylphosphonic acid, phenylphosphinic acid, diphenylphosphonic acid, polyphosphonates, dialkylpentaerythritol diphosphites and dialkylbisphenol a diphosphites; the phenolic derivatives are particularly sulfur-containing compounds such as hindered phenol compounds, thioether compounds, dithioate compounds, mercaptobenzimidazole compounds, thiocarbonylphenylamine compounds, thiodipropionate compounds, etc.; tin compounds such as tin maleate and dibutyltin oxide.

As the hindered phenol compound, Irganox1010 (trade name: manufactured by Ciba-Geigy) or Irganox1520 (trade name: manufactured by Ciba-Geigy) is preferable. The phosphorus-based compounds as the secondary antioxidants are preferably PEP-36, PEP-24G, HP-10 (trade name: manufactured by Asahi Denka Co., Ltd.), and Irgafos168 (trade name: manufactured by Ciba-Geigy Co., Ltd.). The sulfur compound is preferably a thioether compound such as dilauryl thiopropionate (DLTP) or distearyl thiopropionate (DSTP).

The light stabilizer is not particularly limited, and examples thereof include benzotriazole compounds and benzophenone compounds. Further, a radical trapping type light stabilizer such as a hindered amine compound can also be suitably used.

These stabilizers may be used alone or in combination of two or more. The amount of these stabilizers added is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, and still more preferably 0.2 to 2 parts by mass, based on 100 parts by mass of the polyurea resin.

Further, the polyurea resin of the present embodiment may be added with a plasticizer as needed. Examples of the plasticizer include, but are not particularly limited to, phthalic acid esters such as dioctyl phthalate, dibutyl phthalate, diethyl phthalate, butyl benzyl phthalate, di (2-ethylhexyl) phthalate, diisodecyl phthalate, diundecyl phthalate, and diisononyl phthalate: phosphoric acid esters such as tricresyl phosphate, triethyl phosphate, tributyl phosphate, tris (2-ethylhexyl) phosphate, tris (methylhexyl) phosphate, tris (chloroethyl) phosphate, and tris (dichloropropyl) phosphate: fatty acid esters such as octyl trimellitate, isodecyl trimellitate, trimellitic esters, dipentaerythritol esters, dioctyl adipate, dimethyl adipate, di (2-ethylhexyl) azelate, dioctyl sebacate, di (2-ethylhexyl) sebacate, methyl acetylricinoleate: pyromellitic acid esters such as octyl pyromellitate; epoxy plasticizers such as epoxidized soybean oil, epoxidized linseed oil and epoxidized fatty acid alkyl esters; polyether plasticizers such as adipic acid ether ester and polyether; liquid rubbers such as liquid NBR, liquid acrylic rubber, and liquid polybutadiene; non-aromatic paraffin oil, etc.

These plasticizers may be used alone or in combination of two or more. The amount of the plasticizer to be added is appropriately selected depending on the hardness and physical properties required, and is preferably 0 to 50 parts by mass per 100 parts by mass of the polyurea resin.

In addition, an inorganic filler, a lubricant, a colorant, silicone oil, a foaming agent, a flame retardant, and the like may be added to the polyurea resin of the present embodiment. The inorganic filler is not particularly limited, and examples thereof include calcium carbonate, talc, magnesium hydroxide, mica, barium sulfate, silicic acid (white carbon), titanium oxide, and carbon black.

< use >

The polyurea resin of the present embodiment is excellent in various physical properties, and therefore can be used for injection-molded parts (grip parts, steering wheels, storage covers for airbags, watch bands, and the like), extrusion-molded articles (hoses, pipes, sheets, and the like), and is dissolved in a solvent and used for synthetic leather adhesives, skin materials, surface-treating agents, fiber coating agents, various surface-treating agents, various adhesives, and the like. In particular, the polyurea resin of the present embodiment is preferably used for synthetic leather.

< polyurea resin film >

The polyurea resin film of the present embodiment is a polyurea resin film having a thickness of 10 μm to 500 μm, which is obtained by molding the polyurea resin into a film shape.

Specific examples of the polyurea resin film of the present embodiment are not particularly limited, and examples thereof include an extrusion-molded film of the polyurea resin and a cast film obtained by dissolving the polyurea resin in a solvent and applying and drying the solution. The polyurea resin film of the present embodiment is excellent in flexibility, strength, abrasion resistance, chemical resistance, and low-temperature characteristics, and therefore is particularly suitable as a skin material and a surface treatment agent for synthetic leather.

Examples

The present embodiment will be described in more detail below using examples and the like, but the present embodiment is not limited to these examples at all. The analytical methods and physical property evaluations in the following examples and comparative examples were carried out according to the following test methods.

< method for evaluating polycarbonate diol >

1) Hydroxyl number (average hydroxyl number) of polycarbonate diol

The hydroxyl value of the polycarbonate diol was measured in accordance with JIS K1557-1.

2) Number average molecular weight (Mn) of polycarbonate diol

The hydroxyl value was determined by JIS K1557-1, and the number average molecular weight (Mn) of the polycarbonate diol was calculated using the following formula (II).

Number average molecular weight (Mn) ═ 56.1X 2X 1000/hydroxyl value (II)

3) Composition (copolymerization ratio) of polycarbonate diol

A sample of 1g of polycarbonate diol was weighed into a 100ml eggplant type flask, 30g of ethanol and 4g of potassium hydroxide were put into the flask, and the mixture was reacted at 100 ℃ for 1 hour. And cooling the reaction liquid to room temperature, adding 2-3 drops of phenolphthalein into the indicator, and neutralizing with hydrochloric acid. After the neutralized liquid was cooled for 1 hour in a refrigerator, the precipitated salt was removed by filtration, and the filtrate was analyzed by GC (gas chromatography). The GC analysis was carried out by using a liquid chromatograph GC-14B (manufactured by Shimadzu corporation, Japan) equipped with DB-WAX (manufactured by J & W Co., Ltd.) as a column, diethylene glycol diethyl ester as an internal standard, and a hydrogen Flame Ionization Detector (FID) as a detector, to quantitatively analyze each component. The temperature rise curve of the column is as follows: after holding at 60 ℃ for 5 minutes, the temperature was raised to 250 ℃ at 10 ℃ per minute.

The composition (copolymerization ratio) of the polycarbonate diol was determined from the molar ratio of the respective alcohol components detected from the above analysis results.

4) Carbonate group content of polycarbonate diol

The carbonate group content is the amount of carbonate groups contained in 1 molecule of the polycarbonate diol, and is specifically determined by the following formula (III).

Carbonate group content (%) - (carbonate group molecular weight) × (number of repeating units in 1 molecule)/(number average molecular weight of polycarbonate diol) × 100 (III)

(the carbonate group has a molecular weight (-O-C ═ O-) of 60.01.)

The number (n) of repeating units in 1 molecule is determined based on the structure of the following formula (7) using the following formula (IV).

(here, m is the average number of methylene groups, n is the number of repeating units in 1 molecule, and the underlined part represents a terminal group.)

The structure of each segment constituting the polycarbonate diol is determined from the composition of the polycarbonate diol determined from the composition (copolymerization ratio) of the polycarbonate diol. Thus, the number of methylene groups in each of the constituent segments is determined, and the average number of methylene groups (m) is calculated from the ratio thereof.

1 number of repeating units in molecule (n) ═ (number average molecular weight (Mn) — terminal group molecular weight)/(repeating unit molecular weight) (IV)

< method for evaluating polyurea resin film >

5) Tensile breaking strength and elongation at break

A solution of a polyurea resin having a solid content of 20% by mass in N, N-Dimethylformamide (DMF) was applied onto a glass plate, and the resultant was heated at 80 ℃ for 2 hours to prepare a film having a thickness of 40 μm. After 24 hours at room temperature, a specimen having a width of 6.6mm and a length of 60mm was cut out from the film. The tensile breaking strength (MPa) and the elongation (%) at break of the above sample film were measured as the stress at 100 elongation (100% modulus: MPa) in a thermostatic chamber at 23 ℃ under the conditions of a jig interval of 20mm and a tensile rate of 10 mm/min using a Universal Testing Machine (manufactured by Zwick Corp.). The lower the stress at 100% elongation, the softer the film, and the flexibility was evaluated to be good.

6) Chemical resistance

The swelling ratio of the film produced by the same operation as 5) above after being immersed in oleic acid at 23 ℃ for 1 week was measured. The swelling ratio is determined by using the following formula (V). The lower the swelling ratio (%), the more excellent the chemical resistance is evaluated.

Swelling ratio (%) { (mass after test-mass before test)/mass before test } × 100 (V)

7) Wear resistance

The abrasion resistance of the film produced by the same operation as in 5) was measured by using a cone abrasion tester in accordance with the method of JIS K5600-5-8. The change in mass (mg) between the mass of the coated plate before the abrasion test and the mass of the coated plate after the abrasion test (500 revolutions) was measured. The less the mass change (mg), the more excellent the wear resistance was evaluated.

8) Measurement of Low temperature Properties (glass transition temperature)

Using a film prepared by the same operation as 5) above, a test piece having a width of 10mm, a length of 40mm and a thickness of 0.4mm was cut out. A test piece was mounted at a chuck pitch of 20mm using a viscoelasticity measuring apparatus (TA 7000 series, DMA7100, manufactured by Hitachi high-tech Co., Ltd.), and viscoelasticity was measured by raising the temperature from-100 ℃ to 100 ℃ at 5 ℃ per minute. The peak of tan. delta. was read to determine the glass transition temperature (Tg). The lower the glass transition temperature (Tg), the more excellent the low temperature characteristics were evaluated.

< method for measuring average number of isocyanate groups in 1 molecule in organic polyisocyanate Compound >

The average number of isocyanate groups (average number of functional groups) in 1 molecule of the organic polyisocyanate compound is determined by the following formula, based on the content (mass%) of isocyanate groups determined by the method described in JIS K7301-1995 and the number average molecular weight of the organic polyisocyanate determined by measuring the number average molecular weight based on polystyrene by Gel Permeation Chromatography (GPC).

(Property 1) content of isocyanate group

(Property 2) number average molecular weight of organic polyisocyanate

carrier: tetrahydrofuran (THF)

The detection method comprises the following steps: differential refractometer

(Property 3) average number of isocyanate functional groups

[ polymerization example 1 of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirring device were charged 396g (4.5mol) of ethylene carbonate, 144g (1.6mol) of 1, 4-butanediol, and 319g (2.7mol) of 1, 6-hexanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 5 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 1.

[ polymerization example 2 of polycarbonate diol ]

Polymerization was carried out in the same manner as in polymerization example 1 except that 189g (2.1mol) of 1, 4-butanediol and 271g (2.3mol) of 1, 6-hexanediol were used as the apparatus used in polymerization example 1, to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate polyol are shown in table 1. This polycarbonate diol is referred to as PC 2.

[ polymerization example 3 of polycarbonate diol ]

Polymerization was carried out in the same manner as in polymerization example 1 except that 234g (2.6mol) of 1, 4-butanediol and 236g (2.0mol) of 1, 6-hexanediol were used as the same apparatus as in polymerization example 1 to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate polyol are shown in table 1. This polycarbonate diol is referred to as PC 3.

[ polymerization example 4 of polycarbonate diol ]

A polycarbonate diol was obtained by conducting polymerization in the same manner as in polymerization example 1 except that 279g (3.1mol) of 1, 4-butanediol and 224g (1.9mol) of 1, 6-hexanediol were used as the same apparatus as in polymerization example 1. The analysis results of the obtained polycarbonate polyol are shown in table 1. This polycarbonate diol is referred to as PC 4.

[ polymerization example 5 of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirrer were charged 396g (4.5mol) of ethylene carbonate, 234g (2.6mol) of 1, 4-butanediol, and 271g (2.3mol) of 1, 6-hexanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the reaction was carried out at 180 ℃ for 2.5 hours while gradually reducing the pressure to 0.5kPa, whereby the monomer was distilled off to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 5.

[ example 6 of polymerization of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirring device were charged 396g (4.5mol) of ethylene carbonate, 234g (2.6mol) of 1, 4-butanediol, and 260g (2.2mol) of 1, 6-hexanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the reaction was carried out at 180 ℃ for 3.5 hours while gradually reducing the pressure to 0.5kPa, whereby the monomer was distilled off to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 6.

[ polymerization example 7 of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirrer were charged 396g (4.5mol) of ethylene carbonate, 234g (2.6mol) of 1, 4-butanediol, and 236g (2.0mol) of 1, 6-hexanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction was switched to single distillation, and the reaction was carried out at 180 ℃ for 8 hours while gradually reducing the pressure to 0.5kPa, whereby the monomer was distilled off to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 7.

[ polymerization example 8 of polycarbonate diol ]

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 10 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 8.

[ example 9 of polymerization of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirrer were charged 396g (4.5mol) of ethylene carbonate, 207g (2.3mol) of 1, 4-butanediol, 236g (2.0mol) of 1, 6-hexanediol, and 70g (0.4mol) of 1, 10-decanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 5 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 9.

[ polymerization example 10 of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirring device were charged 396g (4.5mol) of ethylene carbonate, 167g (2.2mol) of 1, 3-propanediol, and 260g (2.2mol) of 1, 6-hexanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 5 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 10.

[ polymerization example 11 of polycarbonate diol ]

Polymerization was carried out in the same manner as in polymerization example 1 except that 99g (1.1mol) of 1, 4-butanediol and 378g (3.2mol) of 1, 6-hexanediol were used in the same apparatus as in polymerization example 1 to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate polyol are shown in table 1. This polycarbonate diol is referred to as PC 11.

[ example 12 of polymerization of polycarbonate diol ]

Polymerization was carried out in the same manner as in polymerization example 1 except that 306g (3.4mol) of 1, 4-butanediol and 130g (1.1mol) of 1, 6-hexanediol were used in the same apparatus as in polymerization example 1 to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate polyol are shown in table 1. This polycarbonate diol is referred to as PC 12.

[ polymerization example 13 of polycarbonate polyol ]

423g (4.8mol) of ethylene carbonate, 250g (2.4mol) of 1, 5-pentanediol, and 284g (2.4mol) of 1, 6-hexanediol were put into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirring device. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 5 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 13.

[ polymerization example 14 of polycarbonate polyol ]

Thereafter, the reaction mixture was switched to single distillation, and the reaction was carried out at 180 ℃ for 3 hours while gradually reducing the pressure to 0.5kPa, whereby the monomer was distilled off to obtain a polycarbonate diol. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 14.

[ polymerization example 15 of polycarbonate polyol ]

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 10 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 15.

[ example 16 of polymerization of polycarbonate diol ]

Into a 1L glass flask equipped with a rectifying column packed with a regular packing and a stirring device were charged 396g (4.5mol) of ethylene carbonate, 205g (2.7mol) of 1, 3-propanediol, and 171g (1.9mol) of 1, 4-butanediol. 0.09g of titanium tetrabutoxide was added as a catalyst, and the reaction was carried out for 12 hours while distilling off the resulting mixture of ethylene glycol and ethylene carbonate while lowering the pressure from 10kPa to 2kPa at a reaction temperature of 140 to 160 ℃.

Thereafter, the reaction mixture was switched to single distillation, and the monomer was distilled off by reacting the mixture at 180 ℃ for 5 hours while gradually reducing the pressure to 0.5 kPa. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate polyol is referred to as PC 16.

[ Table 1]

[ example 1]

In a 500mL separable flask equipped with a stirrer and filled with nitrogen gas, 15.74g (0.06 mol) of 4, 4' -methylenedicyclohexyldiisocyanate (hydrogenated MDI, average number of isocyanate groups in 1 molecule: 2.0) and 100g of N, N-Dimethylformamide (DMF) were charged and heated to 40 ℃ to obtain a solution. 140g of N, N-Dimethylformamide (DMF), and 0.0029g of dibutyltin dilaurate added as a catalyst to polycarbonate polyol PC 140g (0.02 mol) were added dropwise to the flask over 30 minutes while stirring the solution. The reaction was carried out at 50 ℃ for 2 hours with stirring to obtain an isocyanate-terminated prepolymer. After the temperature of the solution in the flask was lowered to room temperature, 6.8g (0.04 mol) of isophorone diamine was added as a chain extender, and after 1 hour of reaction at room temperature, 0.5g of ethanol was added as a reaction terminator to obtain a DMF solution (solid content about 20 mass%) of a polyurea resin. A glass plate was coated with an N, N-Dimethylformamide (DMF) solution containing 20 mass% of the polyurea resin as a solid component, and the resulting solution was heated at 80 ℃ for 2 hours to prepare a film of the polyurea resin having a film thickness of 40 μm. After 24 hours at room temperature, various physical properties were evaluated. The evaluation results are shown in table 2.

[ examples 2 to 10]

Films of polyurea resins were obtained in the same manner as in example 1 except that PC2 to PC10 were used as the polycarbonate diol, and the films were subjected to evaluation of various physical properties. The evaluation results are shown in table 2.

[ comparative examples 1 to 6]

Films of polyurea resins were obtained in the same manner as in example 1 except that PC11 to PC16 were used as the polycarbonate diol, and the films were subjected to evaluation of various physical properties. The evaluation results are shown in table 2.

[ Table 2]

Examples 11 to 15 and comparative examples 7 and 8

Films of polyurea resins were obtained in the same manner as in example 1 (using the same molar amount) except that PC3 was used as the polycarbonate diol and the isocyanate and the chain extender shown in table 3 were used, respectively, and evaluation of various physical properties were performed. The evaluation results are shown in table 2.

[ example 16]

A1000 mL four-necked flask equipped with a stirrer, a condenser, a nitrogen inlet tube and a thermometer was charged with 33.3g (0.15 mol) of isophorone diisocyanate (IPDI, the average number of isocyanate groups in 1 molecule: 2.0), polycarbonate diol PC 3100g (0.05 mol), 6.7g (0.05 mol) of 2, 2-dimethylolpropionic acid (DMPA), 6.1g (0.05 mol) of Triethylamine (TEA) and 30mL of Methyl Ethyl Ketone (MEK) under a nitrogen atmosphere, and reacted at 80 ℃ for 2.5 hours to obtain an isocyanate terminated (NCO terminated) prepolymer solution. Next, 342g of deionized water was added thereto, and the mixture was mixed with the prepolymer solution at 35 ℃ to obtain a prepolymer dispersion. A solution containing 1.5g (0.0025 mol) of Ethylenediamine (EDA) as a chain extender in 2.0g of deionized water was added to the prepolymer dispersion, and stirred at 30 ℃ for 1 hour to obtain a mixture. Subsequently, the resulting mixture was heated to 80 ℃ to remove MEK, to obtain an aqueous polyurea dispersion having a solid content of 30% by mass. The aqueous polyurea dispersion thus obtained was poured in a predetermined amount into an aluminum dish, left to stand at room temperature for 24 hours, and then heat-treated at 80 ℃ for 12 hours to prepare a film of polyurea resin having a film thickness of 40 μm. After 24 hours at room temperature, the film was used to evaluate various physical properties. The evaluation results are shown in table 3.

Comparative example 9

A film of a polyurea resin was obtained in the same manner as in example 16 except that PC14 was used as the polycarbonate diol, and the film was subjected to evaluation of various physical properties. The evaluation results are shown in table 3.

[ Table 3]

Industrial applicability

The polyurea resin of the present invention has excellent various physical properties, and therefore, can be used for injection-molded parts (grip parts, steering wheels, storage covers for airbags, watchbands, and the like), extrusion-molded articles (hoses, pipes, sheets, and the like), adhesives for synthetic leathers, skin materials, surface-treating agents, coating agents for fibers, various surface-treating agents, various adhesives, and the like, which are dissolved in a solvent.

Claims

1. A polyurea resin which is a reaction product of a polyisocyanate compound (a), a polycarbonate diol (b) and a chain extender (c),

the chain extender (c) is a diamine,

in the formula (1), R₁Represents a divalent aliphatic hydrocarbon or alicyclic hydrocarbon having 2 to 20 carbon atoms.

2. The polyurea resin according to claim 1, wherein in the (b) polycarbonate diol, 20 mol% or more of the repeating units represented by formula (1) are repeating units represented by formula (2) below, and 20 mol% or more of the repeating units represented by formula (1) are repeating units represented by formula (3) below,

3. the polyurea resin according to claim 1 or 2, wherein the polyisocyanate compound (a) is a cycloaliphatic polyisocyanate.

4. The polyurea resin according to any one of claims 1 to 3, wherein the chain extender (c) is an alicyclic diamine.

5. A polyurea resin film obtained by molding the polyurea resin according to any one of claims 1 to 4 into a film shape, the polyurea resin film having a thickness of 10 to 500 μm.

6. A synthetic leather using the polyurea resin according to any one of claims 1 to 4.